I don't understand the using of RGB in LOVE

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sabino
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I don't understand the using of RGB in LOVE

Post by sabino »

Hi,
I've just bought an e-book titled "LOVE for Lua Game Programming".
I've read some page and I found this code as example:

love.graphics.setColor(0,0,0,225)
love.graphics.setBackgroundColor(255,153,0)

Why the first line has 4 numbers (RGB is identified by only 3 numbers)?
Thank you!
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slime
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Re: I don't understand the using of RGB in LOVE

Post by slime »

Hi!

The fourth argument to setColor controls opacity/transparency when drawing. A value of 255 means fully opaque / no transparency, and a value of 0 means fully transparent. Anywhere in between means partial transparency.
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kikito
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Re: I don't understand the using of RGB in LOVE

Post by kikito »

It's actually RGBA (the A defaults to 255) http://en.wikipedia.org/wiki/RGBA_color_space
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bartbes
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Re: I don't understand the using of RGB in LOVE

Post by bartbes »

And of course the background is RGB, instead of RGBA because your background can't be transparent (what would be behind it?)
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Zilarrezko
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Re: I don't understand the using of RGB in LOVE

Post by Zilarrezko »

bartbes wrote:And of course the background is RGB, instead of RGBA because your background can't be transparent (what would be behind it?)
Conspiracy theory!
jjmafiae
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Re: I don't understand the using of RGB in LOVE

Post by jjmafiae »

Bartbes, I think there might be a secret cookie factory behind it.
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zorg
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Re: I don't understand the using of RGB in LOVE

Post by zorg »

bartbes wrote:And of course the background is RGB, instead of RGBA because your background can't be transparent (what would be behind it?)
What about "what is behind it.", e.g. the desktop, or another window, or both, or whatever... though i'm sure that there would be some nontrivial (like cross-platform/windowing system) problems in implementing this, assuming it'd even be possible.
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